000 AXPZ20 KNHC 042226 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 2205 UTC MON NOV 03 2014 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL ANALYSIS. BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2115 UTC. ...SPECIAL FEATURES... NEWLY DOWNGRADED TROPICAL STORM VANCE WAS CENTERED NEAR 20.4N 108.6W OR ABOUT ABOUT 210 NM...385 KM...SW OF MAZATLAN MEXICO AT 04/2100 UTC MOVING TOWARD THE N-NE OR 030 DEGREES AT 12 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 988 MB. MAXIMUM SUSTAINED WINDS HAVE DIMINISHED TO 55 KT WITH GUSTS TO 65 KT. VANCE IS WEAKENING VERY QUICKLY LATE THIS AFTERNOON DUE TO 50-60 KT OF SW VERTICAL WIND SHEAR...WHICH HAS DISPLACED MOST OF THE CONVECTION OFF TO THE NE...WHERE SCATTERED MODERATE TO STRONG CONVECTION WAS OCCURRING WITHIN 330 NM ACROSS THE NE SEMICIRCLE. RAINFALL TOTALS OF 4 TO 8 INCHES WITH ISOLATED AMOUNTS NEAR 12 INCHES ARE STILL EXPECTED THROUGH WED OVER THE STATES OF SINALOA... NAYARIT....AND DURANGO IN WESTERN MEXICO. THESE RAINS ARE LIKELY TO PRODUCE LIFE-THREATENING FLASH FLOODS AND MUD SLIDES...ESPECIALLY IN AREAS OF MOUNTAINOUS TERRAIN. LARGE SWELLS GENERATED BY VANCE HAVE BEGUN TO AFFECT PORTIONS OF THE COAST OF SOUTHWESTERN MEXICO AND BAJA CALIFORNIA SUR TODAY AND WILL CONTINUE INTO WED. THESE SWELLS WILL LIKELY TO CAUSE VERY LARGE AND DANGEROUS SURF CONDITIONS LEADING TO LIFE-THREATENING RIP CURRENT CONDITIONS. THE RAPID WEAKENING TREND IS EXPECTED TO CONTINUE TONIGHT WITH VANCE WEAKENING TO A TROPICAL DEPRESSION BY THE TIME IT REACHES THE COAST OF MEXICO WITHIN THE NEXT 24 HOURS. HOWEVER...A TROPICAL STORM WATCH REMAINS IN EFFECT FROM MAZATLAN NORTHWARD TO TOPOLOBAMPO MEXICO. SEE THE LATEST NHC FORECAST/ ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP1/WTPZ21 KNHC FOR MORE DETAILS. ...TROPICAL LOWS... A LOW PRES CENTER IS SUGGESTED BY VISIBLE SATELLITE IMAGERY NEAR 14.5N105W AT 1009 MB AND IS MOVING N AT 10 KT. SCATTERED MODERATE ISOLATED STRONG CONVECTION WAS OCCURRING WITHIN 150 NM ACROSS THE N QUADRANT OF CENTER. SE WINDS OF 20-30 KT WITH SEAS OF 7-11 FT ARE OBSERVED WITHIN 210 NM OVER THE NE QUADRANT. ELSEWHERE FROM 09-15N BETWEEN 101-110W WINDS ARE MOSTLY SOUTHERLY AT 10-15 KT WITH SEAS OF 6-9 FT IN MIXED SE AND NW SWELL. SIMILAR BY WEAKER WIND SHEAR THAT IS AFFECTING VANCE IS ALSO IMPACTING THIS LOW AND IT IS EXPECTED TO DISSIPATE BY SUNRISE ON WED. A LOW PRES CENTER NEAR NEAR 10.5N132W IS ANALYZED AT 1009 MB AND IS MOVING SLOWLY W ALONG THE MONSOON TROUGH. THIS LOW HAS MOVED INTO AN AREA OF STRONG MIDDLE TO UPPER LEVEL SINKING MOTION AND IS NOW VOID OF CONVECTION. SOUTHERLY WINDS OF 20-25 KT ARE OBSERVED WITHIN 120 NM OVER THE SE QUADRANT WITH SEAS OF 7-9 FT...WHILE NE-E WINDS OF 20-30 KT WITH SEAS OF 9-12 FT ARE OBSERVED S OF 21N W OF 130W. THIS LOW IS EMBEDDED IN A MUCH LARGER AREA OF TRADES COVERING THE WATERS FROM 09-25N W OF 115W WITH NE WINDS OF 15-20 KT AND SEAS OF 7-11 FT PRIMARILY DUE TO MIXING NW...NE AND SE SWELL. THIS LOW IS EXPECTED TO REACH NEAR 11N135W EARLY WED. BY THEN THE AFFECTED AREA WILL SHRINK WITHIN AREA BOUNDED BY A LINE FROM 29N120W TO 14N115W TO 10N140W TO 23N140W TO 29N120W WITH NE WINDS OF 15-20 KT WITH SEAS 0F 7-10 FT. THE LOW WILL DISSIPATE BY EARLY THU WITH THE AREA OF NE 15- 20 KT TRADES AND SEAS OF 6-9 FT WITHIN THE AREA BOUNDED BY A LINE FROM 20N140W TO 14N130W TO 09N140W TO 20N140W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH AXIS WAS ANALYZED FROM 06N73W TO 09N85W TO 07N97W TO LOW PRES 14.5N105W...RESUMES FROM 13N110W TO LOW PRES 10.5N132W TO 08N140W. SCATTERED MODERATE TO STRONG FROM 04N TO 07N E OF 86W...WITHIN 90 NM OF LINE FROM 07N94W TO 09N100W AND FROM 10N103W TO 12N112W...AND WITHIN 60 NM OF 09N119W AND 13N140W. ...DISCUSSION... GULF OF TEHUANTEPEC...THE GALE CONDITIONS HAVE ENDED ACROSS THE GULF THIS AFTERNOON AS THE ASSOCIATED HIGH PRESSURE OVER THE GULF OF MEXICO HAS BEGUN TO SHIFT E OF THE GULF OF MEXICO BASIN. ALTHOUGH WINDS ARE STEADILY DECREASING THIS AFTERNOON...EXPECT TONIGHTS NORTHERLY DRAINAGE TO SUPPORT A MAXIMUM OF 25 KT. COMPUTER MODEL GUIDANCE IS SUGGESTING THE NORTHERLY FLOW WILL INCREASE TO 20-25 KT BY LATE THU...AND GRADUALLY INCREASE TO 20- 30 KT BY SUNRISE FRI WITH SEAS BUILDING TO 12 FT. GULF OF PAPAGAYO....NE-E 20-25 KT WINDS WITH SEAS OF 5-8 FT WERE OBSERVED WITHIN 45 NM OF LINE FROM 11N86W TO 10N90W...INCLUDING THE GULF OF PAPAGAYO EARLY TODAY AND GENERALLY PERSISTED INTO THE AFTERNOON HOURS. AN AREA OF ENHANCED SEAS OF 7-9 FT IN MIXED N AND S SWELL WERE ALSO OBSERVED WITHIN THE AREA BOUNDED BY A LINE FROM 10N97W TO 10N91W TO 02N97W TO 10N97W. THE DRAINAGE FLOW ACROSS THE GULF OF PAPAGAYO SHOULD ONLY REACH 15-20 KT LATE TONIGHT...AND ONLY 15-20 KT LATE WED NIGHT. THE AREA OF SUBSIDING MIXED SWELL SHOULD BE WITHIN THE AREA BOUNDED BY A LINE FROM 09N97W TO 04N93W 03N98W TO 09N97W WITH SEAS OF 7-9 FT EARLY WED...AND ONLY WITHIN 90 NM EITHER SIDE OF A LINE FROM 08N98W TO 03N96W EARLY THU. .GULF OF CALIFORNIA...NW WINDS OF 20-25 KT WITH SEAS OF 5-7 FT WERE OBSERVED ACROSS THE GULF OF CALIFORNIA TO THE N OF 29N THIS MORNING AND HAVE SINCE BECOMING NW TO N AND SPREAD S TO 28N THIS AFTERNOON. THE PRES GRADIENT HERE IS EXPECTED TO CONTINUE TO TIGHTEN THROUGHOUT THE REMAINDER OF TODAY...SPREADING NW-N WINDS 20-30 KT AS FAR S AS 26N BY SUNSET WITH SEAS BUILDING TO 6-8 FT IN THE LONG FETCH WATERS NEAR 30N113W. THE GRADIENT WILL RELAX WITH NW-N WINDS OF 20-30 KT ONLY ACROSS THE WATERS N OF 28N EARLY WED...WITH WIND CONDITIONS BELOW 20 KT BY EARLY THU. $$ STRIPLING